APA Citation

Keller, P. C. (1990). Gemstones and Their Origins. Boston, MA: Springer US.

Chicago Style Citation

Keller, Peter C. Gemstones and Their Origins. Boston, MA: Springer US, 1990.

MLA Citation

Keller, Peter C. Gemstones and Their Origins. Boston, MA: Springer US, 1990.

Warning: These citations may not always be 100% accurate.